1991 GMC Sierra

1991 GMC SIERRA

192,000 MILES • V8 • 4WD • AUTOMATIC

HUNTERMAN2010

MEMBER
1 POST
FOLLOW

okay the motor and tranny have 30000 on them but when i start it up it starts up hard.... i just put a new starter in it last winter.... i think it might be the fuel pump. but also when it is idling it skips a beat when it idles. also when i am driving down the road and or if i wanna lay it to the rug to feel all the power it doesn't get up and go..... and it doesnt feel like it is getting all of the power it has from the 350 i have in it??????

Sep 16, 2010 at 10:33 PM

RASMATAZ

CAR REPAIR CONTRIBUTOR
75,992 POSTS

Could be caused by one of the following below:

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

If it doesn't apply disregard it and keep testing

Sep 17, 2010 at 2:57 AM

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